Soaring number of Americans are now 401(k) millionaires

Sweet 401(k) balances.

The number of folks with $1 million or more saved in their 401(k) accounts jumped 20% from September to the end of December, according to Fidelity Investments.

All told, there were 422,000 retirement savers in Fidelity 401(k) plans sporting balances of seven figures and beyond as of Dec. 31, up from 349,000 at the end of September and 299,000 at the end of 2022.

There were also 391,562 IRA millionaires on Dec. 31, up from 338,725 at the end of September and 280,320 at the end of December 2022.

"We are encouraged to see retirement balances increase so dramatically this quarter, reflecting the improving market conditions and enabling retirement savers to see significant gains in their account balances and retirement preparedness," Michael Shamrell, vice president of thought leadership for Fidelity Workplace Investing, told Yahoo Finance.

No kidding.

Read more: How to start investing in 2024: A step-by-step guide

Retirement savers ended the year with average account balances at their highest level in nearly two years. Adding to that good juju was that more than a third of workers increased their retirement savings contribution rate in 2023.

That’s according to Fidelity’s fourth quarter analysis of savings account balances for more than 45 million IRA, 401(k), and 403(b) retirement accounts.

If you’re one of the nearly 1 in 4 Americans who don't have a clue how much they have socked away in their retirement accounts, maybe it’s time to take a gander.

You might be pleasantly surprised. Last year was a dream for many Americans’ retirement savings account balances, with the S&P 500 index (^GSPC) up 26.3% and the Dow Jones Industrial Average (^DJI) up 13.7%.

The bigger balances, however, came from a combination of a few things, not just the strong stock market.

At the end of 2023, 78% of 401(k) savers were contributing at a rate high enough to secure the full matching contribution offered by their employer. The total average 401(k) savings rate for the fourth quarter — a combo of employee and employer match contributions — was roughly 14%.

In the fourth quarter, nearly half of individuals increased their contribution of their own volition without waiting for their plan to automatically add a bump up. About 1 in 4 employers offer auto-enrollment now, and the average employer default contribution rate (the amount paid into your retirement account if you don’t make your own selection) is at an all-time high of 4.1%, according to the report.

Mountain range behind is lit by the morning light
The number of folks with $1 million or more saved in their 401(k) accounts jumped 20% from September to the end of December, according to Fidelity Investments. (Getty Creative) · AscentXmedia via Getty Images

401(k) millionaire keys to swelling balances

So, who are these millionaires, and what’s their secret sauce?